Horological regulator



NOV; I 1970 MP ET AL 3,540,211

' HOROLOGICAL REGULATOR Filed May 28. 1969 INVENTORS HA RWEU. B. 7/70MP50N EDWA Rb KA uu vj 3,540,211 HOROLOGICAL REGULATOR Harwell B. Thompson, Cheshire, and Edward Kaulins, New Milford, Conn., assignors to Timex Corporation, Waterbury, Conn., a corporation of Connecticut Filed May 28, 1969, Ser. No. 828,530 Int. Cl. G041) 17/14 US. Cl. 58-109 4 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to horology and more particularly to a hairspring regulator.

In many horological instruments the time base is an oscillator. The oscillator is connected to the inner end of a hairspring and the outer end of the hairspring is attached to a fixed part of the instrument, for example, a frame plate or bridge. In many mainspring driven and electric watches, the oscillator is a balance wheel fastened to a balance staff The staff pivots in bearings or other pivot means.

The timekeeping accuracy of the instrument is dependent upon the balance wheel and its hairspring.

A problem involving the hairspring system arises from the desire that when the horological instrument is sold it should be regulated to keep accurate time. One, way to obtain such an initial accurate regulation is to place a watch on a timing machine, regulate it a first time, allow it to run for a while, for example, a few hours or days, and regulate it a second time. That procedure is time-consuming, costly and may require skilled personnel. In mass production, a watch is placed on a timing machine and the watch regulator moved into its supposedly correct position. However, it has been found that the oscillator rate rapidly drifts off its setting. This rapid initial drift is possibly caused, in insturments using a curbed hairspring, by a change in the effective length of the hairspring due to a change in contact area between the hairspring and the regulator. A curbed hairspring is designed to constantly lie against a wall of the regulator and not to vibrate within the regulators opening. Possibly the hairspring initially rests on one or a few points on the internal surface of the regulator opening; but in its first few hours or days of running it wears down those points and thereby changes the contact area between the hairspring and the regulator. Thus, in the present invention where the contact portion of the regulator arm is substantially less than the width of the hairspring, the effective length of the hairspring and the regulation becomes rapidly fixed.

It is the objective of the present invention to provide a regulator which prevents drifting of the oscillator rate after the regulator is initially adjusted, thereby avoiding a readjustment of the regulator after its initial setting. It is a further objective of the present invention to prevent a change in timekeeping due to the effect of the moving and vibrating hairspring on the regulator.

In accordance with the present invention, a horological I instrument is provided in which an osillator assembly is attached to a hairspring at its inner end. A regulator "United States Patent ice is positioned to contact the hairspring between its inner end and its outer fixed end.

The regulator is constructed. in one alternative, so that the part of the regulator which touches the hairspring is less wide than the width of the hairspring. The area of contact between the regulator and the hairspring is purposely made small so that the initial wearing away does not have an adverse effect. The contact between the regulator and the hairspring determining the effective length of the hairspring is accomplished almost at once. In one embodiment, the regulator arm has a flange-like portion with an opening, the hairspring contacts the regulator on the inner surface of the opening (toward the balance staff), and the contact wall of that opening has a protrusion upon which the hairspring rests. In a second embodiment that inner wall of that opening is V a pin having a shoulder portion of greater diameter than the rest of the pin.

In an alternative construction, the portion of the regulator in contact with the hairspring is made of a resilient (elastic) material. The material is initially compressed by the hairspring, at the point of contact, and presents a relatively large and constant contact area.

Other objectives of the present invention will be apparent from the following detailed description giving the inventors best mode of practicing the invention, the description being taken in conjunction with the accompanying drawings.

In the drawings:

FIG. 1 is a side view, partly in cross-section, of the balance wheel, hairspring and regulator;

FIG, 2 is an enlarged side plan view of a portion of the regulator which is the first embodiment of the present invention;

FIG. 3 is an enlarged view, partly in perspective and partly in plan, of the second embodiment of the present invention; and

FIG. 4 is an enlarged side plan view of the third embodiment of the present invention.

The horological instrument is described in a wrist watch, although the present invention is appicable to other horological instruments using an oscillator and a hairspring.

As shown in FIG. 1, the watch movement includes a balance wheel 10 which is fixed on a balance wheel staff 11. A hub 12 is also fixed on staff 11. The staff pivots between pivots 13 and 14 in frame plate 15 and bridge 16, respectively. A hairspring 17 is connected, at its inner end, to the hub 12. The hairspring 17, at its outer end, is connected to the bridge by means of a wedge pin arrangement 18. A regulator 19 is rotatably mounted on bridge 16 above the pivot 14. The regulator 19 has a regulator arm 20 with an extension flange portion 21 having an opening 22 through which the hairspring passes.

In the regulators of FIGS, 2 and 3 the drawings are only of the outer end of the regulator arms. The remainder of the regulator may be of conventional construction.

In the regulator of FIG. 2, the inner wall 23 of opening 22 is toward the balance staff. That wall includes a central integral protruding portion 24. The hairspring 17 contacts the end of protruding portion 24. The distance the protruding portion 24 protrudes is its height and its vertical distance in FIG. 2 is its width. The vertical distance (the longer side) of the hairspring is its width and the horizontal distance (the shorter side) its thickness. For example, the width of the protruding portion 24 may be .002 in. compared to a hairspring width of .010 in, In all cases the width of that protruding portion is less than the width of the hairspring.

In the regulator of FIG. 3, the regulator arm 20a terminates in an extension flange portion 210! having an opening 22a through which the hairspring 17a passes. A regulator pin 26 consists of a top shank portion 27, a shoulder portion 28 and a bottom shank portion 29. The pin is round in cross-section and the dameter of the shoulder portion 28 is larger than the diameter of the shank portions. The pin 26 is secured to the regulator arm 20a and forms the inner wall of the opening 22a. The enlarged shoulder portion 28 protrudes into opening 22a and the hairspring 17a contacts that shoulder portion 28. In all cases the width of portion 28 is less than the width of the hairspring.

In the embodiment of FIG. 4 the regulator arm 20b has a downwardly descending flange portion 21b having an opening 22b through which the hairspring 17b passes. The inner wall of the opening 22b is formed by a strip of resilient (elastic) material which is adhered to wall 31 of the flange portion. A suitable material is natural rubber. The resilient material may be coated on wall 31 or wall 31 may be entirely of such material. The hairspring 17b contacts the resilient material 30.

In operation, in any of the embodiments the watch is placed on a timing machine and regulated by movement of the regulator. The watch will retain its initial rate, without re-regulation, in the process of its manufacture.

We claim:

1. A horological device having a frame member and bridge, an oscillator assembly, a hairspring connected between the oscillator assembly and the bridge and an adjustable regulator pivotly positioned on the bridge and having an arm positioned to contact the hairspring, the said regulator arm having a portion adapted to contact the hairspring, the said contact portion being substan- 4 tially less than the width of the hairspring to facilitate the intimate engagement of the regulator and hairspring.

2. A horological device as in claim 1 wherein the regulator arm has a downwardly extending flange portion having an opening through which the hairspring passes, and the said contact portion is a protrusion from the wall of the said opening, said protrusion being engaged by the hairspring.

3. A horological device as in claim 1 wherein the regulator arm has a downwardly extending flange portion having an opening, one wall of the opening comprising a pin having a main body portion and a raised shoulder portion intermediate the ends thereof, said shoulder portion being substantially less than the width of the hairspring and being engaged by said hairspring.

4. The horological device as in claim 1 wherein the oscillator assembly includes a balance wheel and a hairspring hub mounted on said balance stalf.

References Cited UNITED STATES PATENTS 2,088,421 7/ 1937 Kohlhagen 58-109 2,209,172 7/1940 Putnam 2 58-109 FOREIGN PATENTS 1,295,468 5/ 1962 France.

674,549 6/ 1952 Great Britain.

304,176 12/ 1932 Italy.

257,460 4/ 1949 Switzerland.

RICHARD B. WILKINSON, Primary Examiner S. A. WAL, Assistant Examiner 

